Ilyas, Sumera I

Abstract Background TOPAZ-1 demonstrated durvalumab + gemcitabine and cisplatin (GemCis) superiority over GemCis in first-line treatment of advanced biliary tract cancers. Real-world data from US patients and patients excluded from TOPAZ-1 (patients with autoimmune conditions [AICs] who did not receive immunotherapy) are lacking. We report real-world data for patients with cholangiocarcinoma treated with durvalumab + GemCis. Methods This retrospective, observational study enrolled adult patients diagnosed with cholangiocarcinoma in the US from the International Cholangiocarcinoma Patient Registry (ICPR) treated with first-line durvalumab + GemCis between 2021–2023. De-identified medical records from ICPR were obtained directly from consenting patients/caregivers. Patient demographics and tumor characteristics (primary objective; assessed at initial diagnosis), comorbidities, second-line treatment modalities, median real-world overall survival (mrwOS), and median real-world time to next treatment (mrwTTNT; initiation of first-line treatment and last activity in the database or death) are reported. Results Seventy patients received first-line durvalumab + GemCis: 13 (18.6%) had AIC(s) and 57 (81.4%) did not. Patient demographics, clinical characteristics, and comorbidities are shown (Table). Median (quartile 1–3) time from diagnosis to start of first-line treatment was 1.0 (0.7–1.7) months; median follow-up from first dose of first-line treatment was 7.0 (3.7–12.1) months. The mrwOS (95% CI) was 15.5 (15.1–not evaluable [NE]) months. mrwTTNT (95% CI) was 10.8 (10.4–15.7) months overall and was 20.8 (10.4–NE) months in patients who died without receiving subsequent treatment (censored at date of last activity). Among patients with AIC(s), <5 received second-line therapy (all received chemotherapy alone). Among patients with no AICs, 15 received second-line treatment; 11 (73.3%) received targeted therapy alone and <5 received chemotherapy alone. Conclusions This dataset demonstrates patients with AIC(s) are treated with durvalumab + GemCis in clinical practice. The mrwOS for durvalumab + GemCis in this patient population is consistent with TOPAZ-1 and global real-world studies.

Abstract Background & Objectives Based on the TOPAZ-I study, durvalumab combined with gemcitabine and cisplatin (GemCis) is now supported as a standard of care treatment for cholangiocarcinoma. Patients with extrahepatic cholangiocarcinoma (eCCA) often have underlying autoimmune conditions (AICs) which could restrict immunotherapy use. Treatment patterns in patients with eCCA with AICs and non-autoimmune conditions (NAICs) are reported. Method This retrospective observational analysis of adult patients diagnosed with eCCA in the United States enrolled in the International Cholangiocarcinoma Patient Registry between 2019 and 2023, focused on those treated with durvalumab. The registry contains de-identified data from medical records obtained directly from consenting patients and caregivers. Patients were followed from index date (date of eCCA diagnosis) until the last activity in the database or death. Demographics, clinical characteristics, biomarkers, treatment patterns, and adverse events (AEs) are reported. Results Overall, 135 patients with eCCA were enrolled: 24 (17.8%) had 2:1 AICs and 111 (82.2%) had NAICs. Baseline demographics were comparable between groups: the median (quartile [Q]l-Q3) age at diagnosis was 63.0 (55.0-70.0) years, the mean number of comorbidities in the overall population was 10.1, and 50.4% of patients were female. PD-Ll positivity was noted in 12.6% of patients and HER2 positivity in 10.4%. Of 91 patients with eCCA who received first-line therapy, 34 (37.4%) received GemCis alone, 27 (29.7%) chemotherapy alone (non-GemCis +/- nab-paclitaxel), 9 (9.9%) GemCis plus nab-paclitaxel, 7 (7.7%) durvalumab plus GemCis, 7 (7.7%) durvalumab monotherapy or in combination, and 7 (7.7%) other regimens. Treatment patterns by autoimmune comorbidity status are also reported (Table). Overall, 129 patients (95.6%) had ≥1 AE; fatigue was the most common (71.1%). Conclusion More patients with eCCA received a first-line durvalumab-based regimen post-March 2022 vs the full study period. The use of durvalumab as first-line treatment in this subgroup may suggest that AICs do not restrict its use.

Abstract Background Cholangiocarcinoma (CCA) is a deadly cancer of the hepatic bile duct epithelial cells. Loss-of-function mutations of epigenetic regulator ubiquitin C-terminal hydrolase deubiquitinase BRCA1associated protein 1 (BAP1) occur in 26-32% of human CCA and are associated with worse prognosis and resistance to cytotoxic therapy. The goal of this study is to identify how BAP1 loss promotes cell death evasion through metabolic rewiring. Materials and methods Isogenic wild-type and BAP1-deficient human and murine CCA cell lines were generated with shRNA/siRNA or CRISPR/Cas9 and were used to assess ferroptosis sensitivity by treatment with ferroptosis inducers. In vitro, ferroptosis was assessed by phospholipid peroxidation (C-11BODIPY), mitochondrial phospholipid peroxidation (MitoPeDPP, MitoCLox), iron overload (MitoFerro green) and cell death (CellTiter-Glo). Phospholipidomics and proteomics were performed in isogenic cells by LC-MS/MS. Syngeneic liver orthotopic CCA murine models and patient-derived xenografts (PDX) were used for in vivo pre-clinical studies. Results Our findings indicate that BAP1 loss confers CCA ferroptosis resistance. BAP1 loss protects CCA against mitochondrial iron overload, ROS accumulation, and phospholipid peroxidation. BAP1 loss protects from mitochondrial phospholipid peroxidation and cardiolipin oxidation. Unbiased phospholipidomic profiling revealed that BAP1 loss remodels membrane phospholipid composition, enriching for ferroptosis blocking monounsaturated phospholipids (MUFA-PLs) at the expense of ferroptosis-inducing polyunsaturated (PUFA-PLs). We found that BAP1 loss upregulates TLCD1, a phosphatidylethanolamine acyltransferase that incorporates MUFAs into membrane phospholipids, thereby stabilizing membranes against peroxidation. TLCD1 knockdown in ferroptosis-resistant BAP1-deficient CCA cells, restored ferroptosis sensitivity. Notably, TLCD1 is significantly upregulated in human BAP1-mutant CCA as compared to BAP1-expressing tumors. While not a mitochondrial protein, TLCD1 localizes in the ER and by the mitochondrial outer membrane, as demonstrated by our immunofluorescence analysis in human CCA cells. From a therapeutic perspective, we developed EpCAM (adhesion molecule highly expressed in CCA cells)-aptamer coated lactosomes packaged with siRNA against glutathione peroxidase 4 (GPX4), as a proof-of-concept strategy to safely induce ferroptosis selectively in CCA in vitro and in vivo. Administration of siGPX4-lactosomes in pre-clinical syngeneic liver orthotopic CCA murine models demonstrated a favorable safety profile, achieved robust intratumoral GPX4 knockdown (>50%), exhibited optimal biodistribution, induced significant tumor lipid peroxidation, and resulted in reduced tumor burden. Lastly, ferroptosis inducer JKE-1674, combined with gemcitabine/cisplatin (Gem/Cis) significantly blocked tumor growth of Gem/Cis-resistant patient-derived xenografts. Conclusions Our findings reveal that BAP1 loss reprograms mitochondrial phospholipid metabolism thus conferring CCA resistance to ferroptosis, identifying TLCD1 as a targetable metabolic vulnerability in BAP1-mutant CCA. Additionally, our findings support ferroptosis inducing compounds as promising therapeutic approaches for CCA.

Abstract Background & Objectives Patients with cholangiocarcinoma (CCA) commonly progress within months on first-line gemcitabine/cisplatin–based therapy with immune checkpoint inhibition (ICI), consistent with the emergence of treatment-induced adaptive resistance. Cellular senescence and its secretory program (senescence-associated secretory phenotype, SASP) can remodel the tumor immune microenvironment. We hypothesized that gemcitabine/cisplatin induces tumor-cell senescence that promotes immunosuppression and progression and prioritized SASP mediators that are mechanistically linked to this phenotype. Method We quantified senescence and lineage markers in chemotherapy-naïve (n = 18) and gemcitabine/cisplatin treated (n = 23) human cholangiocarcinoma specimens and analyzed single-nucleus RNA sequencing in 9 human CCA tumors. In murine orthotopic CCA models, senescent tumor cells were ablated using p16 or p21 promoter restricted inducible apoptosis (ATTAC), followed by immune profiling by flow cytometry in endpoint cohorts, or tested alone and in combination with gemcitabine/cisplatin-based therapy and immune checkpoint inhibition (ICI) for survival cohorts. Conditioned media from proliferating versus senescent tumor cells were applied to bone marrow-derived macrophages (BMDMs) to assess polarization and suppression on CD8+ T-cell proliferation. SASP candidates were screened by cytokine arrays and Growth/Differentiation Factor 15 (GDF-15) was validated by expression and genetic perturbation. Results Senescent cells were enriched in the tumor compartment in human cholangiocarcinoma and increased after chemotherapy, as assessed by p16, p21and telomere-associated DNA foci (TAF). In mice, ablation of p16+ or p21+ senescent tumor cells reduced tumor burden, prolonged survival, and improved response to gemcitabine/cisplatin-based regimens. Chemotherapy-induced senescence increased immunosuppressive tumor-associated macrophages (TAMs), an effect reversed by senescent tumor cell ablation. Mechanically, GDF-15 was the top enriched secreted factor from senescent human CCA cells, tracked with senescence associated transcriptional programs, and decreased after senescent tumor cell ablation. GDF-15 promoted immunosuppressive macrophage phenotype switching and macrophage-mediated suppression on CD8+ T cell proliferation. In comparison, senescence-restricted GDF-15 knockdown reduced tumor growth and macrophage-mediated immunosuppression. Conclusion Chemotherapy-induced tumor cell senescence promotes an immunosuppressive microenvironment through GDF-15 linked macrophage remodeling. Targeting senescent tumor cells or intercepting senescence associated GDF-15 signaling may improve response to first-line therapy in CCA.